Using the principles of operant conditioning, variables will be studied which influence the development, functioning and elimination of oral ethanol as a reinforcer for rats and Rhesus monkeys. Oral ethanol serves as a reinforcer when it is self-administered at rates and volumes which exceed those of its vehicle control, which is usually water. When oral ethanol functions as a reinforcer, it increases the frequency of behaviors which result in its presentation. Methods used in analyzing other reinforcers may be applied to ethanol. Variables that affect both whether and to what extent oral ethanol is a reinforcer may be categorized as past history factors (e.g., prior drug experience), current circumstances (e.g., food deprivation), and response consequences (e.g., ethanol concentration). These variables will be studied parametrically, i.e., across a range of values, and interactions between variables will be explored systematically. The objectives of this research are (1) to investigate functional relations between certain independent variables (e.g., prior ethanol drinking experience) and several dependent variables (e.g., response rate reinforced by ethanol presentation, volume of ethanol consumed); (2) to study interactions between these independent variables (e.g., both ethanol concentration and reinforcement schedule parameter will be varied); and (3) to assess the relative importance of the variables studied. These objectives will have three consequences. One will be the establishment of a nonhuman model of ethanol dependence. A second consequence will be the development of a systematized body of knowledge which may be used in the analysis of the complicated phenomena of human ethanol dependence. A third consequence will be determination of results which can resolve conflicts between published studies that used only a single parametric value for each independent variable (e.g., one ethanol concentration). BIBLIOGRAPHIC REFERENCES: Beardsley, P. and Meisch, R.A. Ethanol intake in food-deprived and food-satiated rats: Effects of ethanol concentration and alternate positions of water and ethanol. Reports from the Research Laboratories of the Department of Psychiatry, University of Minnesota, PR-75-4, 1975.